Abstract: Disclosed are a data transmission system, method, and apparatus, a device, and a medium, used for solving the problem in the prior art of low data transmission efficiency in a remote vehicle diagnostic process. Specifically, a vehicle diagnostic device establishes a UDT communication connection with a remote diagnostic server, and during a data transmission process, the vehicle diagnostic device periodically determines a current congestion value on the basis of a transmission delay between the vehicle diagnostic device and the remote diagnostic server, a network state of the vehicle diagnostic device, and the load capacity of the remote diagnostic server, and according to a target transmission rate corresponding to the current congestion value, sends a UDT data packet encapsulated by data to be transmitted of a target vehicle.

Abstract: Provided are device order data storage method and apparatus, and device order data query method and apparatus.